Switching apparatus with lock-off device



' May 9, 1961 B. R. OSIEJA ETAL SWITCHING APPARATUS WITH LOCK-OFF DEVICEFiled July 28, 1958 INVENTORS JOHN DE TORRE 9 BENJAMIN Rv OSIEJAATTORNEY United States Patent p 2,983,799 SWITCHING TAPPARATUS'WITHLOCK-OFF nnvrcn Benjamin R. 0sieja, Nixon, and John De Torre, Westfield,N.J., assiguors to'Federal Pacific Electric Company, a

The present invention relates to switching apparatus provided with alock-ofi device. A widely known standardized type of switching apparatusincludes a cover and an operating handle that moves in a slot in thecover. An object of this invention is to provide a novel lock-off devicethat can be mounted on such apparatus to receive a padlock forobstructing operation of the handle. A further object of the inventionis to provide such apparatus with a removable lo-ck'ofi device adaptednot only to receive a padlock in position to block operation of thehandle but also wherein the padlock serves the further function ofpreventing removal of the lock-offdevice. Correspondingly, a feature ofthe invention is the provi- ,sion of a novel lock-off for circuitbreakers and switches that can be removed readily when no longer wanted.

The illustrative embodiment described in detail below represents theform presently preferred for achieving the foregoing objects. Furtherobjects and features of novelty will become apparent from the followingdetailed description of the embodiment. This embodiment includes a pairof members hinged together and having overlying portions that havepadlock-receiving holes. The hinged members have projecting portionsthat interlock with the slot and handle of the circuit breaker as theholes in the lock-off are moved into padlock-receiving alignment. As aresult, removal of the lock-oft device from the switching apparatus isprevented so long as a padlock extends through the aligned openings inthe hinged members, and the padlock is positioned in the path of theoperating handle so as'to prevent its operation from off to on or thereverse. When the padlock is removed the lock-off can be readily removedif desired.

The nature of the invention and its further objects and features ofnovelty will be apparent from the following detailed description of theillustrative embodiment which is shown in ,the accompanying drawings. Inthose drawings:

Fig. 1 is the top plan view of an embodiment of the invention; n

Fig. 2 is a side .view of the embodiment in Fig. 1 shown in fragmentarycross-section; and

Fig. 3 is a fragmentary cross-section of the apparatus in Fig. 2.

Thedrawings show 'an embodiment of the invention appliedto a circuitbreaker of the type in Patent 2,673,264 issued March 23, 1954, to ThomasM. Cole. Such apparatus includesa pair of contacts that are operablebetween the off or open position and the on or closed position by anover-centering spring mechanism, including a toggle, that is operated bya handle. The circuit breaker includes a trip-free overload releasemechanism allowing the contacts to open even though the handle may beheld in its on position. A circuit breaker of this form can be used toswitch power on and off, and the identical mechanism may be manufacturedwithout, however, including anoverload release arrangement, in whichcase. the circuit. breaker becomes, simply, a switch. For

this reason, it is convenient to generalize by referring to such switchor such circuit breaker as switching apparatus.

The switching apparatus in the drawings includes a two-part moldedcasing including a base 10 and a cover 12 which enclose the operatingmechanism, the contacts, and the overload release means, description ofall of which is omitted here but is fully described inthe foregoingpatent to Cole. Cover '12 has a slot 14 formed therein, through which ahandle 16 projects. Slot 14 is made long enough so that the handle canbe operated to all of the necessary positions required in circuitbreaker operation. With handle 16 in the position illustrated, thecircuit breaker is off. If, handle 16 were shifted to the extremeright-hand position in slot 14, the circuit breaker would be on. Whenthe overload release mechanism causes automatic opening of the contact,the handle 16 assumes a position somewhat to the left of the on?position. Handle 16 is moved to the extreme right-hand end of slot 14,to reset the overload release mechanism after an overload occurs, toenable later reclosing of the contacts.

Handle 16 has a projecting portion 16a as illustrated, which extendsintegrally from'a molded piece of insulation formed with two arcuateprojections extending in opposite directions from portion 16a. Themolded handle part is carried by a pivoted metal part 18 having apivotal bearing 20. The arcuate handle projections 16a and 16b arecircular segments having their center at bearing 20. Handle 16 has apair of ribs 22 and a pair of grooves 24, and cover 12 has a rib 26,these handle and cover configurations providing a labyrinth path tominimize the possibility of hot gases escaping through slot 14 when thecircuit breaker opens in response to a short circuit and the arc isbeing interrupted. These ribs extend all along the projections 16a and16b of the handle, and cover rib 26 also extends along the fullsegmental extent of the handle 16, in its various operating positions.

A lock-01f device 30 is provided that can readily be mounted on theforegoing switching apparatus. This lock-off device includes a pair ofmembers 32 which are formed of sheet metal that are pivotally joined toeach other by rivet 34. Each member 32 has a leg extending from pivot 34on which an abutment portion 36 is formed and each leg has portion 38projecting beyond its abutment 36. Each projection 38 enters the passageor crevice formed by the cover 12 and the body 16 of the operatinghandle. The projections 38 diverge and extend in generally oppositedirections, so that it is not possible to remove the lock-01f device 30from the switching apparatus without scissoring members 32. Device 30can. be removed from its assembled position as shown in the drawings byallowing the two projecting portions 38 to approach each other as thelock-ofl device is pulled away from the switching apparatus. Conversely,when the lock-01f device is to be mounted in place, the operation isreversed, projections 38 entering the crevice between the operatinghandle and the cover, to the extent limited. by the abutments 32.

In addition to the .abutments 36 and the projecting portions 38, eachmember 32 includes a portion 39 that overlies the corresponding portion39 of the other member 32. Holes 40 are formed in these overlyingportions for receiving the hasp of a padlock 42.

When the lock-off device is in the position illustrated, holes 40 arealigned with each other and are in a position such that, when thepadlock hasp is inserted, it blocks the handle portion 16a from movingits 0 position upward towards its on position; and by like token, if thehandle were in its on position before the padlock was inserted, thehandle portion 16a would be blocked Patented May 9, 96

from being operated into the off position illustrated. The inserted haspof the padlock also makes it impossible to scissor the two members 32 ofthe lock-01f device and thereby prevents the lock-olf device from beingremoved.

It is a feature of the illustrated embodiment of the invention that thelock-01f device can be used with circuit breakers and similar switchingapparatus of standard construction in which :a crevice is provided atone side of an operating handle that swings along a slot in theenclosing cover, without in any way modifying the standard constructionof such apparatus. Of course, such a lockofl? device can also be usedwith similar apparatus. The lock-off device, when mounted on theswitching apparatus in position to receive a padlock for locking thehandle of the switching apparatus, is secured to the switching apparatusas a fixed part of it automatically by the same lock, without using anypermanent supplemental means of attachment. Nevertheless, when thepadlock is removed, the lock-otf device is readily removed from theswitching apparatus. Notably, the manufactured switching apparatus neednot be equipped with an integral lockoff device since the disclosedlock-oil device can be added and removed thereafter as desired. Theswitching apparatus is thereby restored to its previous condition, freeof all vestige of the lock-oil having been used.

The foregoing represents the preferred embodiment of the presentinvention. However, it will be recognized that variations andmodifications as well as varied application of the concepts involved inthe illustrative embodiment will be apparent to those skilled in theart. Accordingly, this invention should be construed broadly inaccordance with its full spirit and scope.

What is claimed is:

1. A lock-off device for the operating handle of a circuit breaker orthe like having a handle that moves along a slot in the enclosure ofsuch device, said lock-off device including a pair of essentially flatsheet metal members pivoted together in overlying relationship andhaving a pair of leg portions suitable to enter the enclosure and toextend beyond the extremities of the slot in the enclosure, said membersalso having a'pair of overlying portions having padlock-receiving holesthat are aligned only when the leg portions are in their extendedpositions, the aligned holes being located to receive a padlock inposition to obstruct the movement of said handle along said slot.

2. -A lock-off device for the operating handle of a circuit breaker orthe like having a handle that moves along a slot in the enclosure ofsuch device, said lock-oil device including a pair of relatively movableessentially flat sheet metal members assembled in overlying relationshipand having a pair of leg portions suitable to enter the enclosure and toextend beyond the extremities of the slot in the enclosure, said membersalso having a pair of overlying portions having padlock-receiving holesthat are aligned only when the leg portions are in such insertedpositions, the aligned holes being located to receive a padlock inposition to obstruct the movement of said handle along said slot.

3. In combination a circuit breaker or the like having a cover, anoperating handle movable along a slot in said cover for opening andclosing the contacts thereof, and a locking device for preventing suchoperation of said handle, said locking device including two relativelymovable members having leg portions extending in opposite directionsthrough said slot alongside said handle, said leg portion extendinginside cover and each having an abutment engaging the extremity of theslot, said members also having overlying portions embodyingpadlock-receiving holes that are aligned only when said leg portions areso extended, said aligned holes being in position to receive a padlockin position to dispose the padlock in the path of said operating handle,said cover and said handle having passages therebetween for admission ofsaid legs only by moving said overlying portions from an initialposition of misalignment of said holes toward and into hole-alignedpositions so that removal of the locking device from the cover requiresreverse pivotal movement of said members and is prevented by a padlockinserted in the aligned holes.

4. In combination, a locking device in assembly with a switching devicehaving an operating handle movable between on and off positions and acover formed with an elongated slot in which said operating handlemoves, said operating handle having an outwardly projecting manuallyengageable portion and oppositely extending internal arcuate portionsunderlying said cover, and a lock-off device removably assembled to saidswitching device and including a pair of sheet metal members hingedtogether, having a pair of oppositely extending legs includingrespective abutment portions engaging the opposite ends of said slot andadditional portions projecting into a space between the cover and theoperating handle, said leg portions having projections extending snuglybetween said cover and said oppositely extending arcuate portions of thehandle when in inserted position and said leg portions having abutmentsengageable with the extremities of the cover slot, said members havingoverlying portions formed with holes that are aligned when saidprojecting portions are in their respective inserted positions, saidaligned holes being in position to dispose a padlock inserted therein inthe path of operation of said handle thereby to block the handle, saidleg portions being removable from the cover only by pivoting saidmembers in relation to each other and thereby moving said holes out ofalignment, whereby removal of said lock-01f device from said switchingapparatus is prevented when said holes are retained in alignment by aninserted padlock.

5. A molded-case circuit breaker having an operating handle extendingexternally through an opening in the casing thereof, and a lock-offdevice assembled thereto, said lock-01f device including a pair ofessentially flat members pivoted together in mutually overlyingrelationship and having projecting portions adapted to extend into theopening and to be separated so as to underlie the casing at oppositeextremities of the opening, said members having respectivepadlock-receiving openings in respective overlying portions thereof thatare aligned with each other only when said projecting portions underliethe casing as aforesaid, said essentially flat lock-oil device beingadjacent to but wholly out of the path of the operating handle and thealigned openings being intermediate the on and 01? positions of thehandle.

6. Molded-case switching apparatus, including a cover having anelongated opening, an operating handle movable therein between on andoff positions and a lockolf device having relatively movable essentiallyflat members including portions adapted to enter the opening and then tobe extended underneath the cover at opposite ends of said opening, saidmembers having respective overlying portions provided withpadlock-receiving openings aligned when said portions are so extended,said essentially fiat lock-off device being disposed adjacent to butwholly out of the path of the operating handle and saidpadlock-receiving openings when aligned being adjacent the path of saidoperating handle between said on and oil positions thereof.

7. A lock-01f device adapted to be mounted on molded-case switchingapparatus including a cover having an elongated opening and an operatinghandle movable therein between on and oif positions, said lock-oildevice having relatively movable essentially flat members includingportions adapted to enter the opening and then to be extended underneaththe cover at opposite endsof said opening, and having shouldersengageable with said opposite ends ofsaid opening to limit movement ofthe device in opposite directions along the elongated opening, saidmembers having overlying portions provided with respectivepadlock-receiving openings aligned when said portions are so extended,said padlock-receiving openings when aligned being adjacent the path ofsaid operating handle between said on and o positions thereof.

8. Switching apparatus including a casing and an operating handlemovable between 0 and on positions and a lock-ofif device mountedthereon closely adjacent to said handle but out of the path of movementthereof between on and off positions, said lock-oif device including apair of relatively movable members having openings movable intoalignment with each other for re ceiving a padlock in obstructingposition between the on and 0E positions of the handle, said membershaving portions that assume interlocking engagement with said casingwhen said openings are in alignment, said members being movable torelease said engagement only by misaligning said openings.

9. In the combination of a lock-oft device mounted on switchingapparatus, in which the switching apparatus includes a casing and anoperating handle movable along a path between oif and on positions, thatimprovement wherein said lock-off device includes a pair of relativelymovable members disposed wholly out of but laterally adjacent to saidpath of said handle, said pair of members having respective openingsformed for receiving the hasp of a padlock only when the openings are inalignment with each other, said openings being disposed at a positionbetween the on and oiT positions of the handle and closely adjacent tobut out of said path of said handle so that a padlock hasp when insertedin the openings is in obstructing position relative to the handle, saidmembers having portions that have interlocking engagement with saidcasing when said openings are in alignment and said members beingmovable to release said interlocking engagement only by misaligning saidopenings in the absence of a padlock hasp.

References Cited in the file of this patent UNITED STATES PATENTS2,169,860 Van Hoom Aug. 15, 1939 2,192,060 Wise Feb. 27,1940 2,663,768Sorensen Dec. 22, 1953 2,832,857 Landmeier Apr. 29, 1958 2,849,552Firestone Aug. 26, 1958

